Background Concentrations Of Heavy Metals Research Articles

Release dynamics, risk evolution and driving mechanisms of heavy metals in superalkaline fly ash co-disposed by MSW landfill

Fly ash from waste incineration is growing rapidly and has become a global problem. Landfill is the main treatment method, but the release behavior of ultra-alkaline fly ash needs further study. In this study, the release pattern of heavy metals from fly ash, the long-term risk after seepage, and the main control mechanisms were explored by indoor simulation experiments and process simulation modeling. The results show that carbonation is the main control mechanism for the release rate of heavy metals from super-alkaline fly ash, and the release rate is slow at the initial stage, but the release concentration of Zn and Pb may increase tens of times with the continuous reaction between the acidic substances in the leachate and the alkaline substances in the fly ash. The heavy metals released into the leachate can cause the concentration of Zn, Cd and Pb in the groundwater to exceed the standard by 39.50, 6.70 and 5.99 times due to seepage. Furnace type is the key controlling factor for background concentrations of heavy metals in ultra-alkaline fly ash, and the exposure concentrations of Cu, Cd, Zn, and Pb in ultra-alkaline fly ash from grate furnaces as well as the GT1 facility are 4.19, 4.19, 4.14, and 37.5 times greater than those of fluidized beds, respectively, with a higher risk of long-term landfill. Regionally, the regional occupancy rate of heavy metal concentrations indicated that the risk of adequate rainfall was high in the southeastern coastal region, which was five times higher than that in the inland northwest. Therefore, the long-term dynamics and risk evolution of Zn, Cd, and Pb in the groundwater around MSWLs in the coastal area should be paid attention to after the landfilling of ultra-alkaline fly ash in order to ensure the safety of the shallow groundwater environment after landfilling.

Background Concentrations of Heavy Metals in the Surface Soil Horizon of Oil and Oil–Gas Condensate Fields in Eastern Siberia

Background Concentrations of Heavy Metals in the Surface Soil Horizon of Oil and Oil–Gas Condensate Fields in Eastern Siberia

Main trends and results of 300-years anthropogenic impact on the geological environment and ecosystem of the Eastern Gulf of Finland

The seafloor of the eastern Gulf of Finland (the Baltic Sea), especially its easternmost part – Neva Bay – has experienced anthropogenic impacts since the beginning of the XVIII century. The aim of this paper is: i) to analyze results of different stages of anthropogenic impact on the geological environment and ecosystem, ii) to assess the influence of dredging, dumping, and aggregates (sand, gravel) and ferromanganese concretions extraction on bottom relief and sedimentation processes, and iii) to establish the major spatial and temporal trends of heavy metal accumulation in the soft bottom sediments. Since the establishment of St. Petersburg, and into the 1960s, there was a physical impact on the seabed through the construction of artificial islands, dredging, and dumping. From 1960s to the 1990s, these types of activity became even more intense, as nearshore submarine terraces were used for sand and gravel extraction, and sediment pollution (e.g., heavy metals) has become one of the main environmental problems of the region. Based on extensive geochemical data collected for the first time in the study area, we examined a vertical distribution of heavy metals in cores obtained from different sedimentary basins. Results demonstrate a trend of increasing concentration values from the 1940s to the 1990s. Background concentrations of heavy metals are based on the geochemistry of catchment areas, decreasing in concentrations from the northwest to the southeast, while the maximum concentrations of hazardous substances deposited from the 1970s to the 1990s were observed in the easternmost part of the gulf. Since the 1990s the heavy metal input to the Gulf of Finland has significantly decreased, so the concentration of these hazardous substances in the surface sediments dropped as well, demonstrating a spatial distribution corresponding more to background (natural, pre-industrial) values. On the other hand, big hydrotechnical projects, realized during the last 20 years – artificial territories and new harbors construction, accompanying with dredging and dumping, ferromanganese concretion extraction, etc. – led to resuspension and secondary pollution of water. The other problem is the expansion of anoxic areas, caused both by climate change and human-stimulated eutrophication. Near-bottom anoxic conditions stimulate heavy metal migration from bottom sediments into the water column. All these processes impacted benthic communities as our review of previously published studies reveals. Geological and geophysical research revealed that within some areas anthropogenic impact caused a complete change of the sedimentation processes such as direction and rates of transport, which led to the total transformation of bottom relief, surface sediment distribution, and the benthic communities.

Assesment of heavy metals concentration in initial soils of post-mining landscapes in Kryvyi Rih District (Ukraine)

Abstract Assessment of heavy metals content in the initial soils of the post-mining landscapes plays an important role in pollution control, ecological protection, and safe-guarding human health. In this study, the site-specific pedogeochemical background contents of several metals in soils in Kryvyi Rih Iron Ore Mining & Metallurgical District (central part of Ukraine) were determined. The metal concentrations in the soils of Petrovsky waste rock dump were also quantified and were also assessed using indices of pollution. The field sampling was carried out at a depth of 0-10 cm in five plots in dump area and in one plot in control site. The 43 soil samples were collected. The results showed that local background concentrations of heavy metals in soils of studied area decreased in the following order (mg×kg−1): Fe (42 510) > Mn (761.7) > Cr (94.48) > Zn (90.51) > > As (31.85) > Cu (28.10) > Pb (18.73) > Co (16.21) > Sn (4.64) > Mo (0.28) > Cd (0.16). In the initial soils of devastated lands at Petrovsky waste rock dumps the predominance of increased Cd, Co, Fe, Mm, Mo and Sn content and the predominance of decreased As, Cr and Pb content were observed. Based on the mean values of the individual indices of pollution (Pollution index, Geoaccumulation index, Enrichment factor, Contamination factor) can be assumed that in these soils As, Cd, Fe, Mo, Pb and Sn are mostly coming from industrial activities. Co, Cr, Cu, Mn and Zn are mostly related to their natural occurrence in devastated lands. The values of integrated indices of pollution (Nemerow pollution index, Pollution load index, Degree of contaminated, Modified degree of contamination) indicated that the initial soils of post-mining landscapes can be evaluated as no polluted – and extremely heavy polluted.

АНАЛИЗ ЗАГРЯЗНЕНИЯ ТЯЖЕЛЫМИ МЕТАЛЛАМИ МЯГКИХ ТКАНЕЙ ДВУСТВОРЧАТЫХ МОЛЛЮСКОВ В ВОДОЕМАХ Г. ГОМЕЛЯ И ПРИЛЕГАЮЩИХ ТЕРРИТОРИЙ

Currently, observations of the components of aquatic ecosystems - hydrobionts and bottom sediments with the ability to deposit pollutants - are of particular importance. Comprehensive studies of the behavior of heavy metals in aquatic ecosystems are relevant and make it possible to provide an integral assessment of the state of the water body, determine the probability of secondary pollution, find out the migration paths of pollutants, and therefore their implementation is relevant. The article deals with the analysis of quantitative data on the content of heavy metals in the soft tissues of mollusks living in the reservoirs of Gomel and adjacent territories. An array of data was obtained for the period of research in 2010-2021, on the basis of which the choice of an ordinary pearl barley (Unio pictorum L.) as an object of monitoring studies of the ecological state of water bodies was justified. The change in the content of copper, lead and nickel in the tissues of the studied mollusk species during the period of research from 2010 to 2021 indicates a change in the physicochemical conditions in the studied reservoirs, as well as a change in the content of biologically accessible metal forms in water and bottom sediments of aquatic ecosystems. This fact confirms the presence of different routes of entry of heavy metals into the body of different species of bivalve mollusks, as well as the different availability of metal compounds in components of the same aquatic ecosystem for different species of mollusks. As a result of the analysis of the array of data obtained from 2010 to 2021, the authors determined the background concentrations of heavy metals in the tissues of common pearl barley living in the reservoirs of Gomel and adjacent territories: for lead - 0.17 mg/kg, zinc - 19.20 mg/kg, copper - 0.71 mg/kg, manganese - 1084.22 mg/kg, cobalt - 0.25 mg/kg, chromium - 0.71 mg/kg, nickel - 0.95 mg/kg. Patterns of change in the quantitative content of heavy metals in the soft tissues of molluscs are shown.

Evaluation of Heavy Metals Contamination in Suspended Sediments of Dikrong River, Assam, India

This study is a comprehensive monitoring survey to assess the environmental pollution status of the river Dikrong -was carried out in 2020. Samples were taken at 10 different positions along the river from the foot hill of Arunachal Pradesh down to the Brahmaputra river. Besides other biological and chemical parameters, concentrations of Fe, Al, Ti, Pb, Zn, Cu, Ni, Co, Mn and Cr. Very high element concentrations were determined at only a few stations of the river Dikrong. The mean concentration exhibits positive correlations among Fe, Al, Ti, Mn, Zn, Pb, Ni, and Co. The relative distributions of the contamination are: Al > Fe > Ti > Mn > Cu > Cr > Zn > Pb > Ni > Co. An evaluation of the pollution status of the river was carried out by enrichment factors (EFs), contamination factors (CFs), geo-accumulation indexs (Igeo) and pollution load indexs (PLIs) calculated using adapted background concentrations of heavy metals in the sediments. The investigating factors suggest the significant contamination for Dikrong river sediments are Al and Fe. The mean concentrations of heavy metals in the sediments were found to be below the geochemical background level of world surface rock average. The elemental correlation is indicative to the metamorphosed pyrophanite (MnTiO3) deposition.

Remediation mechanism of \u201cdouble-resistant\u201d bacteria\u2014Sedum alfredii Hance on Pb- and Cd-contaminated soil

BackgroundConcentrations of heavy metals continue to increase in soil environments as a result of both anthropogenic activities and natural processes. Cadmium (Cd) and lead (Pb) is one of the most toxic heavy metals and pose health risks to both humans and the ecosystem. Therefore, effectively solving the problem of heavy metal pollution is the concern of soil workers. Among the existing remediation techniques, only the combined use of microorganisms and plants for remediation of heavy metal-contaminated soil is the greenest and most developed one. Consequently, based on this background, this study investigates the remediation mechanism of Pb and Cd heavy metals using the combined action of bacteria and Sedum alfredii Hance.MethodsIn order to enrich the research theory of combined plant and microorganism remediation of heavy metal-contaminated soil, we constructed a heavy metal composite pollution remediation system by combining Pb and Cd-tolerant bacteria with the Pb and Cd hyperaccumulator plant—Sedum alfredii Hance to investigate its combined remediation effect on Pb and Cd composite contaminated soil.ResultsThe results showed that resistant bacteria were able to promote enrichment of Pb and Cd in Sedum alfredii Hance and J2 (200 ml of bacterial solution) was significantly (P < 0.05) more effective than J1 (100 ml of bacterial solution). The resistant bacteria were able to alleviate the toxic effects of Pb and Cd heavy metals on Sedum alfredii Hance and promote growth while reducing rhizosphere soil pH. The resistant bacteria were able to significantly reduce the effective state of Pb and Cd in the rhizosphere soil (P < 0.05), with the greatest reduction in the effective state of Pb in treatment A (Cd7Pb100 mg/kg), where J2 was reduced by 9.98% compared to J0, and the greatest reduction in the effective state of Cd in treatment C (Cd28Pb400 mg/kg), where J2 was 43.53% lower than J0. In addition, the resistant bacteria were able to increase the exchangeable state Cd content by 0.97 to 9.85%. The resistant bacteria had a weakly promoting effect and a highly inhibitory effect on the absorption of Pb by Sedum alfredii Hance.ConclusionsThe resistant bacteria can change the rhizosphere environment and significantly improve the remediation effect of Sedum alfredii Hance on heavy metal cadmium. The role of “double-resistant” bacteria in promoting the accumulation of Cd was greater than that of Pb.

Heavy metal contamination in surface sediments from lakes and their surrounding topsoils of China.

Due to rapid urbanization, industrialization, agricultural development, and mining activities, soil heavy metal pollution has become a severe issue in China. To explore the regional heavy metal ecological risk of lake sediment and surrounding topsoil, we analyzed 237 lakes, with 1797 lake sediment sampling points and 1164 surrounding topsoil sampling points. Lower mean concentrations were detected for most heavy metals in soils than sediment (except for Hg). Cd and Hg in sediments and soils showed a more significant variation, with the coefficient of variation exceeding 110%. Linear regressions and Pearson's correlation analyses demonstrated that sediments and soils exhibited significant positive correlations. The principal heavy metals exceeding the Agricultural Soil Control Standard (ASCS) in sediments and soils were As and Cd, respectively. The Yunnan-Guizhou Plateau Lake Region (YGPLR) was the most seriously affected, exceeding the ASCS for Cd. The lakes with the most severe pollution were located in YGPLR impacted by the high background concentration of heavy metals in soil and mineral development activities. The Eastern Plain Lake Region, the Southeast Lake Region, and the Northeast Plain and Mountain Lake Region showed a clear anthropogenic impact. Lakes in the Inner Mongolia-Xinjiang Lake Region and the Tibetan Plateau Lake Region were estimated to have relatively low ecological risks due to their sparse population and slight environmental disturbance. The impact of geochemical factors on the ecological risk of heavy metals in lake sediments is more substantial than that of human activities at the regional scale.

Rapid estimation of heavy metals in crude oil contaminated soils by X-ray fluorescence (XRF) spectroscopy

Crude oil exploration and exploitation activities in the Niger Delta, Nigeria have caused the contamination of numerous land sites. A total of 45 sub-surface soil samples were collected from three genuinely crude-oil spill sites and their heavy metal concentrations were measured using X-Ray fluorescence spectroscopy. The range of measured heavy metal concentrations (mg/kg) in the three study sites are as follows: chromium (Cr) 54-75, copper (Cu) 5.4-16.6, iron (Fe) 14841-23404, lead (Pb) 13.5-21.4, manganese (Mn) 158-555, zinc (Zn) 32.6-47.2 in Site 1; Cr (35-66), Cu (5-16.1), Fe (10166-20967), Pb (12-17.8), Mn (209-440), Zn (17.6-33.6) in Site 2; and in Site 3: Cr (32-115), Cu (6.5-20.8), Fe (7538-22800), Pb (12-135), Mn (98-338), Zn (19.9-177). The trend of heavy metals contamination in the three sites are as follows: Fe &gt; Mn &gt; Cr &gt; Zn &gt; Pb &gt; Cu. Their mean concentrations were relatively higher than background concentrations of heavy metals in soils previously reported in same region. Using the contamination factor (CF), the intensity of heavy metal (Mn, Cr, Zn, Pb, and Cu) contamination in soils from the three oil spill sites were evaluated and compared. The index showed Cr &gt; Mn across the three sites, which was highest in site 1 and least in site 2. The trend of CF varies for the other metals. The high values of CF for Mn and Cr show that Mn and Cr have extreme level of contamination while Cu, Pb, and Zn lie within the range of moderate level contamination. Furthermore, statistical analyses shows significant (p &lt; 0.05) correlation between the concentrations of the metals, which indicates the link between the metals. Thus, crude-oil spill may be the common denominator for the heavy metal pollution in the study locations. Based on the contamination indicator parameter, the soils of the studied sites are threatened by contamination of Cr and Mn.

DISPERSAL TRENDS OF THE INVASIVE SPECIES ALPINE PENNY-CRESS (NOCCAEA CAERULESCENS, BRASSICACEAE) IN KARELIA, NW RUSSIA

An invasive species, Alpine penny-cress (Noccaea caerulescens (J. Presl & C. Presl) F. K. Mey.) was for the first time encountered in the Republic of Karelia in the Town of Sortavala in 1909. Over the past 110 years, the species has become quite frequent in the northern Ladoga area, with a fairly rapid dispersal across the area observed before WWII. Further advance of the species to the north and east of this territory has obviously slowed down, although occasional findings have been reported from the very north of the republic (Pyaozersky settlement) and east of Lake Onego (Lobsky settlement). Such a pattern of the species’ current distribution in Karelia can be attributed to the geochemical characteristics of the northern Ladoga area. This territory is rich in heavy metal deposits and ore occurrences, has numerous and extensive outcrops of the crystalline basement, and, as a result, its soils feature elevated background concentrations of heavy metals. Being a metallophyte, N. caerulescens found itself in a favorable environment here. Nevertheless, there is reason to expect further spread of the species across the region.

Heavy metals content in soils of Western Siberia in relation to international soil quality standards

Russian soil quality standards (maximum permissible concentrations) exist only for Mn, Pb and V out of the many heavy metals (HMs) indicative of soil pollution resulting from hydrocarbon mining. This paper presents a comparative analysis of the total content of Ba, Cr, Cu, Ni and Zn as well as Mn, Pb and V in background soils of Western Siberia (Russia) in relation to the wider range of available internationally recognised assessment criteria. The criteria used include the increase in abundance of elements relatively to the upper part of the continental earth's crust, their levels in background soils of other countries and their threshold concentration values for soils of residential and/or agricultural areas in soil quality standards (SQSs) of Netherlands, Germany, the USA and Canada. Specified countries have similar soils and background concentrations of HMs and well-developed methodologies for soil quality assessment. It is concluded that Cu, Ni and Zn levels in West-Siberian background soils are harmless for an ecosystem and human health, while Ba, Cr, Mn, Pb and V concentrations in some of the soils studied are above threshold values (ThVs) and, therefore, require special attention through further assessment. The studied Retisols, Phaeozems and Chernozems of Western Siberia are characterized by the following range of mean concentrations (mg kg−1) of HMs in topsoil: Ba 373–1360, Cr 5–212, Cu 5–100, Mn 50–1800, Ni 7–100, Pb 5–35, V 5–180, and Zn 10–135. In preliminary assessment of contaminated soils within a coniferous forest and forest-steppe ecosystems of Western Siberia, it is most suitable to use the following national ThVs for HMs (mg kg−1): Canadian Pb (45), German Ni (140) and Cr (400) and Dutch Cu (96) and, considering the local geochemical background (especially for the folic horizon of Retisols), it is also appropriate to use Russian Mn (1500), Canadian Zn (200) and Dutch Ba (890). An eluvial pattern of vertical differentiation is typical for total Cr, Cu, Ni, Pb, Zn in Retisols, Ni and Pb in Phaeozems and Cr, Ni and Pb in Chernozems. In topsoil of background landscapes at Western Siberia, total Mn (in all soils studied), Cu (in Phaeozems), Zn (in Phaeozems and Chernozems), as well as mobile Mn (in Retisols and Phaeozems), Ni (in Retisols) and Zn (in Phaeozems) accumulates.

Оценка фоновых концентраций тяжелых металлов и других химических элементов в донных отложениях малых озер юга Карелии

Оценка фоновых концентраций тяжелых металлов и других химических элементов в донных отложениях малых озер юга Карелии

Background Concentrations of Heavy Metals in Brown Algae from the Northwest Sea of Japan

Background concentrations of Fe, Mn, Cu, Zn, Pb, Cd, and Ni were calculated for brown algae Costaria costata from the northwest Sea of Japan. Also the paper contains refined data on heavy metal concentrations in the widespread distributed brown algae, such as Stephanocystis crassipes, Sargassum pallidum and S. miyabei. As the upper threshold levels of metal background concentrations, the median values plus double medians of absolute deviations from the medians were used (Me + 2MAD). The lower threshold level of the background concentration equal to the physiological need for an element is the median of 15% minimum values in the sampling minus the double median of absolute deviations from the median (Me15 - 2MAD15). The calculated ranges of the background concentrations of metals in algae were compared with concentrations of elements in mac-rophytes collected from habitats with background concentrations of metals in water.

Heavy Metal Concentration in the Water and Sediment of the Lake Greenwood Watershed

We report on the concentration of heavy metals (cadmium, chromium, cobalt, copper, iron, and lead) in the water and sediment of Lake Greenwood and the streams and creeks that flow into the lake. Our results show heavy metal concentrations well below levels that were reported in 2012. The heavy metal concentrations reported for Lake Greenwood were on the order of the established background levels; our measurements indicate that heavy metal concentrations are now well below the established background levels. The concentration of heavy metals in creeks sediment and lake sediment was not statistically different for most metals (copper was statistically different). This significant drop in concentration suggests that the major flooding which occurred in 2015 has drastically altered the heavy metal profile of Lake Greenwood and the creeks which flow into the lake. The effect of introducing large volumes of relatively unweathered sediment has an observed lowering of the concentration of heavy metals. For all metals at all sites, the measured concentration of heavy metals in water samples collected was below the screening level established by the US Environmental Protection Agency. Also, our results also call into question the continued use of previously established background concentration of heavy metals after a significant flooding event, as the addition of large volumes of fresh sediment from flooding events significantly changes the heavy metal concentration.

Use of Background Concentrations of Heavy Metals for Regional Monitoring of Soil Contamination by the example of Rostov Oblast

In the monitoring of soils contaminated with heavy metals, the choice of the target indicators (background or threshold values) is a challenging task. The determination of the background concentrations is of practical importance, because the pollution of clean soils to the levels below the maximum permissible concentration (MPC) or the tentative permissible concentration (TPC) levels is not recorded and, hence, cannot be prosecuted. Background concentrations are rarely applied in pollution assessment, because they remain unknown in most cases. The study of the soils of specially protected natural areas in Rostov oblast has revealed the regional specificity of the soil cover—elevated concentrations of a number of heavy metals and other trace elements—related to their high concentrations in the parent materials. Therefore, it is impossible to apply current public health standards based on the total concentrations of elements, such as MPC and TPC, in the monitoring of soil contamination in Rostov oblast. The use of background values characterizing the soils of specially protected natural areas seems to be more promising for this purpose. For an adequate environmental monitoring, data on the background concentrations of trace elements in the virgin of slightly transformed soils of specially protected natural areas should be obtained with due account for the regional diversity of soils including their classification position, texture, and the character of parent materials.

Determination of heavy metal background concentration in bottom sediment and risk assessment of sediment pollution by heavy metals in the Hrazdan River (Armenia)

The purpose of this study is to determine background concentrations of heavy metals in bottom sediments, as well as to characterize potential danger of heavy metals in bottom sediments of the Hrazdan River. Linear regression method was used to determine background concentrations of metals in bottom sediments. While using this method, the linear regression of determining metal with a comparative element was used: The cobalt was chosen as a relative element, which is conditioned by the absence of significant sources of cobalt in this river. Risk assessment index of Hakanson was calculated for evaluation of bottom sediments contamination by heavy metals. It is obtained that in this part of the Hrazdan River basin potential ecological risk caused from bottom sediments contamination by heavy metals is not high.

Simulation of spatially-distributed copper pollution in a large river basin using the ECOMAG-HM model

ABSTRACTThe semi-distributed physically-based model ECOMAG-HM was developed to simulate cycling of heavy metals in large river basins: on the surface, and in soil, groundwater and river water. The model was applied to study the spatial distribution and temporal dynamics of copper concentrations in watercourses of the Nizhnekamskoe Reservoir watershed in Russia. This watershed is characterized by high background concentrations of heavy metals due to wide occurrence of ore deposits and considerable concentrations of ore-parent elements in rocks. The model was found to adequately reproduce the spatial variation of the mean annual copper concentrations at different monitoring points of the river network. The mean annual specific copper washoff, with the surface and subsurface components of river runoff, and the total copper washoff from the watershed into the river network were calculated and mapped. The contributions of natural and anthropogenic factors to river water pollution by copper were evaluated.

Background Contents of Heavy Metals in Soils and Bottom Sediments in the North of Western Siberia

Background concentrations of heavy metals (Cu, Zn, Ni, Co, Fe, Mn, Cr, Pb, Hg, Cd, Ba, Sr, and Sc) in soils and bottom sediments were determined for the background and anthropogenically disturbed (oil and gas extraction) areas in the north of Western Siberia on the basis of long-term studies (1993–2017). It was found that the soils are characterized by relatively low concentrations of heavy metals. The major factors affecting the variability of the chemical composition of the environmental components are the lithological and chemical composition of the parent materials and the zonal–azonal geochemical differentiation related to peat accumulation. The statistical analysis and the method of ranked geochemical spectra suggested that background element concentrations should be separately determined for organic soil horizons, for mineral (illuvial) horizons in coarse-textured and heavy-textured soils, and for peatlands. Minimum concentrations of most of the studied heavy metals were determined in peatlands: they were 2–8 times lower than the concentrations of these metals in the clayey and loamy illuvial horizons. Mercury and cadmium were the exceptions: their concentrations in the peatlands were 3–4 times higher than those in the illuvial mineral horizons. Background metal concentrations in bottom sediments were separately calculated for three categories: clay and peaty clay sediments, silts, and fine-grained sands. Metals concentrations in clay sediments were significantly higher than those in sandy sediments: by 11 times for Fe and Mn; by 8.5 times for Ni; by 6.5 times for Co; and by 5 times for Zn, Cu, Cr, and V. The concentrations of metals were determined by the ICP MS method. The obtained data on the background concentrations of heavy metals can be recommended for the assessment of technogenic impact on local soils and bottom sediments in the course of the environmental monitoring.

THE INVESTIGATION OF THE OBJECTS OF THE PAST ENVIRONMENTAL DAMAGE ON THE VILKITSKY ISLAND (KARA SEA)

The research of the objects of the the past environmental damage on the Vilkitsky Island located in the Kara Sea. The central part of northern coast where the abandoned objects of the air defense point and the polar station are located is subject to technogenic influence. Around them and on the bank of the Kara sea there are dumps for solid household and industrial waste. Water bodies on the affected part of the island s are polluted with oil and heavy metals. Water quality corresponds to 4, 5 and 6 classes (polluted, dirty and very dirty). Concentrations of oil and heavy metals in the bottom sediments of reservoirs exceeding levels of pollution in the background sites accordingly in 17 and 3, 7 times are found out. In soils of the island’s background sites oil are not found out, and the concentration of heavy metals are extremely low - in 1,6–5 times lower than in a the continental tundra zone and at 2–12 time lower than in the midland of Russia. The background concentration of heavy metals established on the basis of a representative sample in sandy tundra soils can be of interest for the subsequent researches of other Arctic territories combined by young marine sediments. At the polluted sites admissible level of the maintenance of oil is exceeded by 1,3–6,7 times. The content of heavy metals is dominated by soils polluted to an admissible and moderately dangerous level, and in some cases — dangerous and extremely dangerous level. The polluted sites are restricted; the passports of the objects of the past environmental damage were compiled for them. Recommendations about carrying out of actions about liquidation of the past environmental damage are made.

Dust pollution and its potential health risk exposure to inhabitants of Covenant University and canaanland, Ogun state, Nigeria

Understanding the background concentration of heavy metals in dust samples is so much important for identifying and managing pollution. Thus, these concentrations in dust can be distributed indoors and outdoors in order of magnitudes. This study demonstrates the risk analysis of dust samples collected from selected buildings in both Covenant University and Canaanland using Atomic Absorption Spectrometer (AAS). The obtained concentrations were used to determine the Geo-accumulation, Contaminant Factor and the Pollution Loading Index (PLI). The highest geo-accumulation index and pollution loading index of 3.108 and 0.5836 due to chromium (Cr) contents in the dust samples were noted in Lecture Theatre 2 (LT2). The higher values found in LT2 may be due to the wide open of both doors and windows. Both the Geo-accumulation Index and Pollution Load Index were found to be lower than the permissible level suggested by World Health Organization (WHO) and United State Environmental Protection Agency (USEPA). Significantly, these observations from this study will provide the basis for the background concentrations and potential risks of some important heavy metals of environmental concern